MR of craniocerebral hemiatrophy.

The magnetic resonance (MR) findings of three patients with cerebral hemiatrophy, the so-called Dyke-Davidoff-Masson syndrome, which is characterized by variable degrees of unilateral loss of cerebral volume and compensatory changes of the calvarium are presented. The condition was due to middle cerebral artery stroke in all patients. The pathologic alterations of cerebral tissue and the brainstem were reflected in detail on the MR studies. MR findings in addition to the primary vascular insult included prominence of the cortical sulci and perimesencephalic cistern in one subject with acquired infarction, but an absence of such generalized sulcal prominence in two cases of congenital infantile paralysis. Otherwise the secondary ipsilateral pathologic observations were quite similar in the patients with congenital and acquired ischemic disease and encompassed a unilaterally small cerebral hemisphere together with ipsilateral diploic calvarial expansion, elevation of the petrous bone and orbital roof, and hypoplasia/atrophy of the cerebral peduncle. Although computed tomography (CT) and MR are complimentary, it is felt that MR represents the imaging procedure of choice with respect to the assessment of the etiology and extent of cerebral parenchymal involvement in patients presenting with a clinical combination of congenital or early onset of seizures, hemiparesis/plegia, and/or craniofacial asymmetry.